Traditional methods for closing tissue wounds or incisions include the use of sutures, clips, or staples. While such techniques are generally adequate in sealing tissue wounds or incisions, they have associated problems that limit their use. For example, the use of sutures, clips or staples in closing tissue wounds can often lead to scar formation, infection, and a multitude of immunological responses. Tissue incompatibility with sutures, clips, or staples may cause fistulas, granulomas, and neuromas that can be painful and difficult to treat. Sutures, clips, or staples may also tend to cut through weak parenchymatous or poorly vascularized tissue. Additionally, sutures leave behind a tract that can allow for leakage of fluids and can provide a convenient entry point for a variety of organisms.
The success of traditional methods in sealing tissue wounds or incisions also is very dependent on the skill of the practitioner performing such methods. The manual dexterity and eyesight of the practitioner impose severe limits on the use of sutures, staples, and clips, especially when microsurgery is being performed.
An alternative to traditional methods for sealing tissue wounds or incisions is the use of compositions suitable for tissue welding. By "tissue welding" it is meant that an energy source is used to excite the composition, which results in the sealing or closure of the tissue wound or incision. Typically, a tissue welding composition will be applied to the area of the tissue that requires sealing. Upon excitation by an energy source, the composition fuses to the tissue, and the bonding between the composition and the tissue allows the severed parts of the tissue to be proximal to each other, much in the same way as when sutures, staples, or clips are used. Such tissue welding compositions are absorbable within a few weeks and, therefore, do not cause tissue scar formation.
Despite the general advantages that tissue welding has over the more traditional methods, current compositions used in tissue welding suffer from numerous drawbacks. Compositions presently in use solubilize in physiological fluids after application and before excitation by an energy source. Blood dilution of the composition after application, but before excitation, alters the shape and rigidity of the composition as it existed when the composition was applied to the tissue. Such alterations to the shape and rigidity of the composition prior to excitation change the energy absorption characteristics of the composition and weaken its repair tensile strength. The result is an impairment of the reliability and reproducibility of the tissue welding technique.
In view of the foregoing problems, there exists a need for a tissue welding composition that is not soluble or has a low solubility in physiological fluids prior to excitation by an energy source. The present invention provides such a composition and a related method of use. These and other advantages of the present invention, as well as additional inventive features, will be apparent from the description of the invention provided herein.